JSON Formatter
Prettify, minify and validate JSON with a single click. Fully client-side and private.
What is the JSON Formatter?
The JSON Formatter pretty-prints, validates and minifies JSON in your browser. Paste a compact one-liner and get back an indented structure that is easy to scan; paste broken JSON and the tool points to exactly where the syntax fails.
Because everything runs client-side, sensitive payloads such as API responses or config files never travel to a server.
How to use the JSON Formatter
- 1Paste your raw JSON into the input area.
- 2Choose an indent style (2 spaces, 4 spaces or tab).
- 3Click "Format" to beautify or "Minify" to strip whitespace.
- 4If the input is invalid, fix the position shown in the error message.
- 5Copy the result or download it as a .json file.
Key features
- Instant formatting with configurable indentation
- Minification for compact production payloads
- Built-in validator that pinpoints syntax errors
- One-click copy of the output
- Handles multi-megabyte payloads client-side
Important notes
- Formatting and minifying only change whitespace — the data itself is never altered.
- If your JSON has a syntax error, the tool reports it instead of guessing; fix the highlighted position and try again.
- Everything is processed in your browser, so your JSON is never uploaded.
Frequently asked questions
What if my JSON has comments?
Standard JSON forbids comments, so they are reported as syntax errors. Strip them before formatting.
Is there a size limit?
The practical limit is your browser's memory — typically tens of megabytes.
Can I use it offline?
Yes — once the page has loaded, formatting works without an internet connection.
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